You don't need to remove the drawers. If you don't want to lock the top drawers, open the top hatch, open each drawer a bit, close the top hatch, and close the drawers. The drawers are now free opening.

If you want to re-secure the drawers, open the top hatch, push each drawer in as far as it will go, then close the top hatch.

The top hatch links with a flat sliding bar that slides through the drawers when they are fully closed. It's intended to be optional / switchable on the fly. The drawers should still close all the way with the hatch closed, however they just won't lock.